1. Field of the Invention
The present invention is generally in the field of semiconductors. More particularly, the invention relates to the packaging of semiconductor dies.
2. Background Art
Switch-mode power converters, such as synchronous power converters, are well known. A synchronous power converter may typically include a control power transistor and a synchronous (sync) power transistor connected in a half-bridge and a driver integrated circuit (IC) for driving the control and sync power transistors. It is desirable to form a synchronous power converter in which a control power transistor, a sync power transistor, and a driver IC are monolithically formed on a common die (i.e. a monolithic die). Among other advantages, such a monolithic die would allow for packaging that is smaller and easier to assemble than a synchronous power converter having more than one die.
The monolithic die can have a high side power input, a low side power input, and a power output of the half-bridge. One approach to assembling the monolithic die in a package would be to connect to the high side power input, the low side power input, and the power output using bond wires. However, in order to achieve low resistive and inductive connections for the monolithic die, many bond wires must be attached to the monolithic die. As such, assembling the monolithic die in the package would become complex and costly. Furthermore, bond wires can be prone to lift-off due to, for example, mechanical stress that can cause the bond wires to fail. Additionally, bond wires can interfere with placement of a heat sink to dissipate heat from the monolithic die.
It would be desirable to provide for a monolithic die in a power converter package that can achieve low resistive and inductive connections for the monolithic die, without use of bond wires for connection to a high side power input, low side power input, and power output of the monolithic die.